A universal personal communication system is a system enabling anyone to communicate instantly with anyone else anywhere in the world. One of the crucial problems of such a system would be locating millions of moving customers in an efficient manner. The existing techniques for locating moving customers in the system are paging and registration using a central database. Considering the large number of customers in a global system, the first technique, if applied without knowledge of the location of the customers is impractical. The registration technique, which records all the movements of customers in a central database, is also impractical because the task of keeping track of such a huge number of users would be immense. Thus, a need exists for a system for efficiently tracking customers in a universal personal communication system.
Furthermore, frequency spectrum reuse is maximized by providing a communication system with cells as small as possible. However, for a moving customer, movement from cell to cell can cause extensive updating of a location data base.
Additionally, communications systems such as a personal communication systems (PCS) having small cells coupled through a hierarchy of nodes must co-exist with existing communication systems during its establishment. The initial establishment of a complete hierarchy of nodes including national and global nodes may not be possible at the initial introduction of the system in some cases. Thus, what is needed is a method for connecting calls between developed hierarchical trees of the communication system when the trees are not related by hierarchical nodes.